Safety assembly for impact-actuated well tool



June 3, 1969 J. c. KINLEY ET L 3,447,504

SAFETY ASSEMBLY FOR IMPACT'ACTUATED WELL TOOL Sheet of Filed July 15,1967 a ywimw m X aw .0 Wu b 7 J... fi w .& 1 9 LHMKYI Q 32 .m 1. rEV I IIHHI HMW% .fillllllI/HU m C m. w fi/f Hfi n xmw Y fi B 0 7 0 J7 a A ax.1 n \rkt.

June 3, 1969 J. c. KINLEY ET AL 3, 4

SAFETY ASSEMBLY FOR IMPACT'ACTUATED WELL TOOL Filed July 13, 1967 wsglia

I N VEN TORS June 3, 1969 J. c. KINLEY ET AL 3,447,604

SAFETY ASSEMBLY FOR IMPACT-'ACTUATED WELL TOOL Filed July 1-3, 1967Sheet INVENTORS BY K muwef United States Patent 166-63 Claims ABSTRACTOF THE DISCLOSURE A safety assembly for use in an impact-actuated welltool such as an explosive perforator wherein the explosive is detonatedby impact and wherein an interference means positively prevents thetransmission of impacts on the tool to the explosive or similar portionof the tool until the tool has been set in the firing or activeposition.

This application is a continuation-in-part of United States patentapplication Ser. No. 623,866 filed Mar. 17, 1967, now abandoned.

Background of the invention The field of this invention is well toolswhich are fired or actuated by impact. Examples of such tools are shownin United States Patent Nos. 2,544,601, 3,199,287 and 3,199,594.

Summary of the invention In some circumstances it may be desirable toimpart a downward jar or impact to an impact-actuated well tool to moveit downwardly in a well pipe past obstructions such as caused by crookedtubing, deposits of scale, a pipe nipple, and the like. In otherinstances, when the tool is lowered on a wireline with a link-type jaror rein jar above the tool, a downward jar and inadvertent firing of animpact-actuated tool may occur upon a lowering of the tool into wellfluid or a restriction in the well pipe.

With the present invention, the well tool may be hit with blows to moveit downwardly as necessary without risk of premature firing ordetonation of the explosive. Also, premature firing of the explosive dueto a closing of a link-type jar or rein jar upon entering fluid or arestriction in the well is prevented. Until such tool has been activatedto an active or firing position by tripping in a collar of the wellpipe, or otherwise, the blows will not cause a firing of the explosive;

An object of the invention is to provide a new and improved impactactuated well tool, and safety assembly therefor, wherein prematurefiring or actuation of the well tool is prevented even though impactsare imparted to the tool for moving the tool downwardly in a well pipeprior to tripping the tool to an active or firing position.

Brief description of the drawings FIG. 1 is a view, partly in elevationand partly in section, illustrating the apparatus of this invention asit is being lowered into a well pipe or casing;

FIG. 2 is a view similar to FIG. 1, but illustrating a perforator of thetype with which the present invention is used after the perforator hasbeen tripped and is therefore ready for firing;

FIG. 3 is a view similar to FIGS. 1 and 2, but illustrating thesubsequent position of the apparatus after the explosive has been firedand the perforator has inserted an insert into the Well pipe or casing;

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FIG. 4 is a view, partly in elevation and partly in section,illustrating in detail the safety assembly of the present inventionwhich is disclosed in the perforator of FIGS. 1-3 and illustrating theassembly in a latched or inactive position;

FIG. 5 is a view similar to FIG. 4, but illustrating the safety assemblyof this invention in the active or firing position;

FIG. 6 is a view illustrating a modified safety assembly which may beused in place of the safety assembly of FIGS. 4 and 5 in the tool ofFIGS. l-3 and illustrates the safety assembly in the inactive or latchedposition; and

FIG. 7 is a view of the apparatus of FIG. 6 after it has been tripped tothe active or firing position.

Description of the preferred embodiments In the drawings, the letter Adesignates generally the perforator or other apparatus of this inventionwith which the safety assembly S of this invention is employed. Theapparatus A, as illustrated in FIGS. l-3, is a well perforator which isadapted to be lowered into a well pipe or casing P having a collar orother recess forming portion C (FIG. 1). The apparatus A is adapted tobe lowered on a wireline W to a suitable elevation in the pipe or casingP for the detonating or firing of the explosive in the apparatus A, forthereby inserting an orifice or other insert X into the pipe P. Theapparatus A is detonated or actuated by means of a weight H which may bein the form of a heavy metal sleeve which is adapted to slide downwardlyon the wireline W (FIG. 3) for causing an impact on the top of theapparatus or tool A. With the present invention, as will be more fullyexplained, the safety assembly S prevents a firing or actuation of thetool A even though the weight or weights H are dropped for the purposeof forcing the apparatus A downwardly within the pipe P or for any otherreason prior to the time for the actuation of the tool A.

Although the safety assembly S of this invention may be used with otherwell tools, it is illustrated with the perforator A by way of example.The perforator A has a perforator body 10 which has a bore 10a in whichis disposed a driving wedge 11 having an inclined wedge surface 11a. TheWedge 11 is disposed below an explosive 12 and a firing pin 14thereabove. A primer cartridge 15 is disposed between the firing pin .14and the explosive 12 in the usual case. The wedge 11 is held in itsupper position by the rear surface 16d of an orifice insert X having abody 16. A shear pin (not shown) holds the insert body 16 and theorifice insert X therewith until the wedge 11 drives downwardly upon theexplosion of the powder or explosive 12. The wedge surface 11a thusforces the body 15 and the insert X laterally to force the orificeinsert X into the well pipe or casing P as illustrated in FIG. 3.

The wedge 11 is stopped'in its downward movement by a stop wedge 20having a surface 20a which is complementary to the inclined surface 11a.Preferably, the stop wedge 20 is divided with a channel or port 20bhaving grease or other lubricant therein which is fed downwardly througha lower passage 21 to a piston 22 so that upon completion of theperforating operation, the piston 22 is forced downwardly into contactwith the upper end of a positioning finger or lever 25. The lever 25 isconventional and is pivotally mounted on a pivot pin 26 so that it isheld in a retracted position (FIG. 1) during the lowering of theapparatus A into the well pipe P. A retaining dog 27 is mounted belowthe lever 25 and holds it in the retracted position of FIG. 1 so long asa shear pin 26 extends from the dog 27 into the body 10. A pivot pin 27ais disposed through a slot 27b so that when the shear pin 28 is severed,the dog 27 drops below the lower end of the lever 25 and thereafter aleaf spring 30 or similar element urges the lever 25 to an extendedposition 3 such as illustrated in FIG. 2. In the extended position, thelever 25 is adapted to seat at its lower surface 25a on the annular edgeof a collar or joint C as will be more evident hereinafter.

The safety assembly S, in its preferred form, is illustrated in FIGS. 4and 5. In such form, the perforator body 10 is connected to a safetybody 30 by threads 10a or other suitable securing means.

A connector sleeve 31 is secured to the upper end of the safety body 30by means of shear pins 32 or other suitable means so that under somecircumstances it is possible to remove the sleeve 31 from the safetybody 30 in the well to expose the fishing neck 30a on the safety body 30for subsequent fishing operations. The connector sleeve 31 carries ahammer body or element 33 which is connected by threads 33a or othersuitable means to a rope socket or connector 34 which has the wireline Wconnected thereto. During the lowering operation, the hammer element 33is maintained in its upper position by a shear pin 34 which is shearedby the downward impact of the weights H so as to move the hammer head33b into engagement with the top end of a firing rod 35.

The firing rod 35 is longitudinally movable within a longitudinal bore30b of the safety body 30, and its upper end 35a is preferably disposedlow enough so that the lower end 33b of the hammer element 33 cannotcontact such end 35a in the inactive or latched position.

The firing rod 35 is held in such inactive or latched position (FIG. 4)by a latch-tripping element 40 which is disposed in a lateral slot 30cthrough the body 30. The element 40 is pivotally mounted on the safetybody 30 by a pivot pin 41 which is positioned in an elongated slot 40a.A shear pin 42 extends through the element 40 and into the safety body30 for maintaining the element 40 in the position shown in FIG. 4, whilepermitting it to pivot upwardly or counterclockwise as viewed in FIG. 4,as will be more fully explained. A resilient member such as a coilspring 43 is connected from the safety body 30 to the element 40 forurging it in a clockwise direction with respect to the pivot pin 41. Asillustrated, the spring 43 is secured to the element 40 by a screw orretaining rivet 44 and it is secured to the body 30 by a screw or bolt45. It will be appreciated that other resilient means may be utilizedfor maintaining the element 40 in its extended position as shown in FIG.4. When the element 40 is in the extended position shown in FIG. 4, thelongitudinal dimension of the element 40 is less than the distance fromthe lower end 35b of the firing rod 35 to the upper end 14a of thefiring pin 14. Therefore, even though blows are imparted through thehammer element 33 to the firing rod 35, they cannot be transmitted tothe firing pin 14. It is to be noted that the firing pin 14 is made intwo sections 14 and 14', but the firing pin could be made in one sectionif desired.

The element 40 has a tripping finger 40b therewith which extendsoutwardly and which is adapted to engage the inner surface of the wellpipe P as the tool A is lowered into the pipe P. During such lowering,the external surface 400 engages the inside of the pipe P and causes apivoting of the element 40 in a counterclockwise direction as viewed inFIG. 4 in opposition to the force of the spring 43. However, upon anupward movement of the apparatus A so as to position the finger 40b in acollar, joint, or other recess of the pipe P, the upper edge 40d isadapted to engage the collar and impart a clockwise force to the element40 to sever the shear pin 42. When the pin 42 is severed, the spring 43causes the element 40 to swing downwardly to the position shown in FIG.so that its longer dimension then is disposed between the lower end 351;of the firing rod 35 and the upper end 14a of the firing rod 14 and itsextension 14'. It is also to be observed that the firing rod 35 isforced slightly upwardly in the preferred form of the invention so thatthe upper end 45a of the rod 35 is in a position for contact by thehammer head 33b when the hammer 4 head 33 is moved downwardly by impactsor blows from the dropping of the weight or weights H. The tool A isthus in the firing position as shown in FIG. 5 so that the impacts fromthe weight or weights H are transmitted through the firing rod 35, theelement 40, and the firing pins 14 and 14' to the explosive 12.

In the preferred operation of the tool or apparatus A, it is lowered onthe wireline W until the safety assembly S is passed below the collar orjoint C at the elevation for perforation. Thereafter the wireline W ismoved upwardly to initially cause the finger 40b to engage in the collarC and trip same to the released or active position of FIG. 5.Thereafter, a continued upward movement of the tool A causes a trippingof the dog 27 so that the lever 25 moves to its extended position (FIG.2). The apparatus A may then be lowered to seat the lever 25 in thecollar C. The sliding sleeve weight or weights H may then be dropped, orthe line W may be otherwise manipulated using jars and/or weights suchas a linktype or rein jar connected to the wireline W above theapparatus A to impart a jarring blow or blows to the tool A for firingthe explosive 12. As explained, the jars or impacts are transmittedthrough the hammer 33 to the firing rod 35 and then through the element40, the firing pin or pins 14 and 14, to the primer cap 15 and then theexplosive 12.

The explosion which occurs in the explosion chamber where the explosiveis located forces the wedge 11 downwardly and forces the insert Xlaterally to penetrate the pipe P as shown in FIG. 3.

The wedge 11 is stopped in its descent by the stop wedge 20 and in doingso, the lubricant or other material in the passages 20b and 21therebelow is forced downwardly to move the piston 22 into contact withthe lever 25 to cause it to retract and thereby cause the entire tool Ato drop from its seated position in the collar C. This drop in theapparatus A causes an increased weight at the surface which indicates tothe operator that the tool has been fired.

In the alternate form of the invention illustrated in FIGS. 6 and 7, thesafety assembly S1 is suitable for use in place of the safety assembly Sin the tool A. Thus, the safety assembly S-l has a safety body which hasthreads 133a at its upper end for threaded engagement with the ropesocket or connector 34 which is attached to the wireline W. The safetybody 130 has a firing rod 135 connected therewith and formed as a partthereof at its lower end. The firing rod 135 is disposed immediatelyabove the firing pin 14, but is spaced therefrom when the firing rod 135is in the latched or inactive position (FIG. 6).

The lower end of the safety body 130 and the firing pin 135 extend intothe bore of an adapter body 50 which has external threads 50a which areadapted to be engaged with the threads 10a of the perforator body 10(FIG. 4).

The adapter body 50 may be formed in numerous ways, but as illustrated,it has an internal annular shoulder 50b which is adapted to receive asplit collar 51. The split collar 51 is of a diameter sufficient to restupon the lateral shoulder 50b, and it is therefore secured to the safetybody 130 by a shear pin 52. Therefore, until the shear pin 52 issevered, the body 130 cannot move downwardly relative to the adapterbody 50. The split ring 51 is retained in position by a retaining sleeve53 which is threaded or otherwise secured at 53a. A stop-latch ring 55is mounted at the upper end of the sleeve 53 and is preferably providedwith an annular inclined surface 55a, the purpose of which will bedescribed.

The safety body 130 is provided with a lateral slot 1300 in which isdisposed a latch lever which is pivotally mounted on a pivot pin 60 sothat it can pivot from the position shown in FIG. 6 to the positionshown in FIG. 7. The lower end 140a of the lever 140 is adapted toengage the inclined surface 55a of the latch ring 55 when the tool is inthe inactive or latched position. A leaf spring or other resilient means143 engages the upper end of the pivoted latch rod or lever 140 toconstantly urge it in a clockwise direction.

The clockwise rotation of the lever 140 is prevented during the loweringof the tool A into the pipe P by means of a tripping finger 14% whichhas an elongated slot 140a. A pivot pin 141 secures the tripping finger14011 in position in the slot 130s. The tripping finger 1401) is urgedto the extended position shown in FIG. 6 into contact with a shear pin142 by means of the spring 143 which is acting against the lever 140. Asuitable stop 63 is provided within the .slot 1300 to limit thecounterclockwise pivoting of the trip lever or finger 14% as the tool Ais lowered into the well. Thus, as the tool is lowered into the wellwith the safety assembly -1 in the tool instead of the safety assemblyS, the surface 140C remains in contact with the inner surface of thepipe P at all times and the finger 1401) is in the extended position,normally slightly pivoted in a counterclockwise direction from thatshown in FIG. 6.

When the tool A is pulled upwardly so that the upper surface 140d of thetripping finger 14011 engages in a collar, joint, or other recess in thepipe P, the shear pin 142 is sheared or severed so that the trippingfinger 14% is rotated by the action of the spring 143 to the inactiveposition shown in FIG. 7. Also, after the tripping finger 1401) has beenreleased to its inactive position of FIG. 7, the spring 143 can thenpivot the interference or latch lever 140 from its latching position ofFIG. 6 to its released or firing position of FIG. 7. It is to be notedthat the safety body 130 has a recess 1307 into which the lower end ofthe lever 140 extends so that the lever 140 is completely retracted andmay move downwardly without interference or contact by the adapter body50 or any part connected therewith.

Subsequently, blows imparted to the tool A with the weight or weights Hare transmitted to the safety body 130 to shear the pin or pins 52 andto thereafter move the firing rod 135 into contact with the firing pin14 as illustrated in FIG. 7. Such a blow causes the explosive 12 to bedetonated as previously explained so that the tool is thus actuated.

The foregoing disclosure and description of the invention areillustrative and explanatory thereof, and various changes in the size,shape, and materials as well as in the details of the illustratedconstruction may be made within the scope of the appended claims withoutdeparting from the spirit of the invention.

We claim:

1. In a well tool having a firing pin for firing an explosive, theimprovement residing in a safety assembly for preventing accidentalfiring of the explosive, comprismg:

(a) a safety body having a longitudinal firing rod therewith;

(b) means for mounting said firing rod in an inactive positionlongitudinally aligned and spaced above said firing pin but movabledownwardly to an active position wherein impacts on the firing rod aretransmitted to the firing pin;

(0) interference means to prevent movement of said firing rod into saidactive position,

(d) tripping means adapted to be tripped upon an upward movement of thewell tool in the well for moving said interference means to permitmovement of said firing rod to said active position; and

(e) said interference means supporting said firing rod in said inactiveposition prior to tripping said tripping means and being interposedbetween and in contact with said firing rod and said firing pin aftertripping said tripping means.

2. The structure set forth in claim 1, wherein:

(a) said interference means forms a part of said tripping means; and

(b) said interference means supports said firing rod in said inactiveposition above said interference means prior to tripping said trippingmeans.

3. The structure set forth in claim 2, wherein said interference meansand said tripping means includes:

(a) a latch-tripping element having an elongated slot;

(b) a pivot pin extending from said safety body through said slot forpivotally mounting said latch-tripping element for pivotal movementthereof on said safety body;

(0) said element having a longitudinal dimension between said firing rodand said firing pin which is less than the distance between said rod andsaid pin when said element is in a latched position; and

(d) said element having a longitudinal dimension when pivoted to afiring position which is at least equal to the distance between saidfiring rod and said firing pin.

4. The structure set forth in claim 2, wherein said interference meansand said tripping means include:

(a) a latch-tripping element having an elongated slot;

(b) a pivot pin extending from said safety body through said slot forpivotally mounting said latch-tripping element for pivotal movementthereof on said safety body;

(c) said element having a longitudinal dimension between said firing rodand said firing pin which is less than the distance between said rod andsaid pin when said element is in a latched position;

(d) said element having a longitudinal dimension when pivoted to afiring position which is at least equal to the distance between saidfiring rod and said firing P (e) a shear pin extending through saidelement and into said safety body; and

(f) resilient means connected from said safety body to said element forurging it to pivot about said shear pin until said pivot pin stopsfurther pivoting of said element by engagement with the wall of saidslot.

5. The structure set forth in claim 1, wherein said firing rod ismounted in a longitudinal bore of said safety body for longitudinalmovement relative thereto.

References Cited UNITED STATES PATENTS 2,629,445 2/1953 Dill 166-55 X2,871,946 2/1959 Bigelow 166-64 3,105,549 10/1963 Raulins 166-63 X3,157,119 11/1964 Porter 166-63 X 3,180,261 4/1965 Moore -456 X3,199,287 8/1965 Kinley 166-63 X 3,366,179 1/1968 Kinley et a1 166-553CHARLES E. OCONNELL, Primary Examiner. IAN A. CALVERT, AssistantExaminer.

US. Cl. X.R. 10221.8; 166-553; 175-456

